Thread forming chaser supporting and adjusting means



.May 31., 1938. .1 s. BARTEK 2,119,036

THREAD FORMING CHASER SUPPORTING AND ADJUSTING MEANS Filed July so, 1936FEE-4 INV R. John 5 Z Q I ZBK ATTORNEY.

Patented May 31, 1938 UNITED STATES PATENT OFFICE THREAD FORMING CHASERSUPPORTING AND ADJUSTING MEANS Application July 30, 1936, Serial No.93,438

2 Claims.

My invention relates to thread forming chaser supporting and adjustingmeans, with more particular reference to a type of construction whichemploys a circular chaser, and has for its object to afford a simple andpractical arrangement that enables accurate adjustment of the chaser onits supporting block.

A more particular object of the invention is to provide a chasersupporting block adapted to receive a circular chaser, which can bereadily positioned therein after grinding, and its operating positiondetermined by a fine adjustment mechanism effective to bring the cuttingedge into proper relation to the center line of the machine.

A further purpose of the invention is to afford a constructionpermittinga fine adjustment of the chaser on its supporting block, andmounting the chaser and adjusting mechanism in such fashion on the blockthat the helical angle of the thread that is out is determined by theangular relation of the chaser to the block on which it is mounted.

To these and other ends, the invention consists in the construction andarrangement of parts that will appear clearly from the followingdescription when read in conjunction with the accompanying drawing, thenovel features being pointed out in the claims following thespecification,

In the drawing:

Fig. 1 is an end elevation of a die head showing the application theretoof one embodiment of the invention;

Fig. 2 is a plan view of the same;

Fig. 3 is a side elevation, partially in section, of one of thesupporting blocks, and its chaser secured in position;

Fig. 4 is a plan view of one of the supporting 40 blocks with the chaserremoved;

Fig. 5 is a bottom plan view of the same;

Fig. 6 is an end elevation of the adjusting plate, and

Fig. 7 is an end elevation of the chaser.

Referring more particularly to the drawing, in which like referencecharacters refer to the same parts throughout the several views, Idesignates a die head which may be of conventional form and providedwith a series of transverse slots 2 50 Within each of which is mounted achaser supporting block 3 that abuts the outer face of the head I and.has a flange l engaging and guided in the slot or guideway 2. Theseveral chaser supporting blocks are movable transversely in the slotsor guideways 2 for the opening and closing operations of the die headand are also removable from the die head when different chasers arerequired, all of which forms no part of the present invention and is inaccordance with known types of automatically-opening die headstructures.

In the present arrangement, each chaser supporting block 3 is providedwith a circular type hollow chaser, set at an angle to the longitudinalaxis of the supporting block and die head, and the block is providedwith means for effecting a fine adjustment of the chaser thereon whilemaintaining the predetermined angular relation between the chaser andthe supporting block.

To accomplish this, the supporting block is provided with a threadedopening 5 disposed at an angle to the longitudinal axis of thesupporting block when the latter is positioned in the head, as indicatedin Fig. 5, said opening 5 being adapted to receive a clamping screw 3which acts to hold the chaser on the block. The hollow chaser isdesignated at '1, having cutting elements arranged parallel, andperpendicular to its longitudinal axis, and the chaser is. provided atits front end with a recess to receive the head 8 of the clamping screw.The clamping screw 6 extends through a sleeve 9 that is provided with aseries of longitudinally extending serrations arranged exteriorlythereof and which engage corresponding serrations II] in the interior ofthe chaser I and thus lock the sleeve to the chaser.

A portion of the sleeve 9 extends beyond the chaser I, as shown in Fig,3, and this part of the serrated sleeve 9 extends within an opening II]in the adjusting plate I I, the opening in which is similarly serratedto lock the sleeve 9 in relation thereto. The adjusting plate IIincludes oppositely extending arms I2 which underlie the overhangingportion I3 of the supporting block, and said portion I3 is provided withthreaded openings I4 that receive the adjusting screws I5. The latterengage the two arms or extensions I2 of the adjusting plate, and areoperable to move said adjusting plate in one direction or the other tobring the cutting edge of the chaser in exactly the proper relation tothe opposite chaser and to the center line of the machine. The openingsI i which receive the adjusting screws iii are disposed in a linelocated at an angle to the outer face of the head and the adjacent faceof the supporting block, as shown in Fig. 4, corresponding to the angleat which the chaser is set on the supporting block, so that theadjusting screws will be brought into proper cooperation with the armsI2 on the adjusting plate II.

With this arrangement, the chaser is provided with cutting elementsextending annularly therearound and arranged at right angles to thelongitudinal axis of the chaser, the helical angle of the thread beingdetermined by the angular position of the chaser on its supportingblock. The chaser is removed from the supporting block for grinding byloosening the clamping screw 8, and after grinding, the chaser andserrated sleeve 9 are positioned within the serrated opening of theadjusting plate ll so as to bring the cutting edge [6 of the chaser toits approximate proper position, and it is then adjusted accurately tobring its cutting edge in proper relation with the center line of themachine by turning one or the other of the adjusting screws l5. Thisrocks the sleeve 9 about the clamping screw 8 and with it the chaseruntil the desired position of the latter is obtained, whereupon the.clamping screw 8 is tightened, while the screws l act' to hold thechaser in its adjusted relation on the supporting block and preventturning of the same.

While the invention has been described with reference to a particularstructural embodiment, it is not confined to the details herein shown,and this application is intended to cover any modifications ordepartures coming within the purposes of the improvement or the scope ofthe following claims.

I claim:

1. The combination with a support, of a circular chaser, a clampingscrew extending through the chaser and securing it to the support, asleeve within the chaser surrounding said screw, an adjusting platesurrounding said sleeve and having an oscillatory movement therewitharound the screw, the sleeve having exterior serrations engagingcorresponding serrations in openings of the same diameter in the chaserand in the adjusting plate for locking said parts together, and means onthe support for rocking the adjusting plate about the screw in oppositedirections and holding it in adjusted position.

2. The combination with a support, of a circular chaser, a clampingscrew extending through the chaser for securing it to the support, asleeve surrounding said clamping screw and provided with exteriorserrations engaging corresponding serrations in the chaser, an adjustingplate also surrounding said sleeve and having corresponding serrationsengaging therewith whereby the adjusting plate and chaser are locked tothe sleeve, the serrated portions of the sleeve within the chaser andadjusting plate being of the same diameter and the adjusting platehaving oscillatory movement about the screw for adjustment, oppositelyextending arms on said adjusting plate, and adjusting screws threaded inthe support and engageable with said arms for rocking the adjustingplate in opposite directions and looking it in adjusted position.

JOHN S. BARTEK.

